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docs/ikev2-howto-zh.md

@@ -58,12 +58,21 @@ Libreswan 支持通过使用 RSA 签名算法的 X.509 Machine Certificates 来
      ikev2=insist
      rekey=no
      fragmentation=yes
-     forceencaps=yes
      ike=3des-sha1,aes-sha1,aes256-sha2_512,aes256-sha2_256
      phase2alg=3des-sha1,aes-sha1,aes256-sha2_512,aes256-sha2_256
    EOF
    ```
 
+   还需要在该文件中添加一行，根据 Libreswan 的版本而不同。请运行以下命令：
+
+   ```bash
+   $ if /usr/local/sbin/ipsec --version | grep -qs -F "3.19"; then
+       echo " encapsulation=yes" >> /etc/ipsec.conf
+     else
+       echo " forceencaps=yes" >> /etc/ipsec.conf
+     fi
+   ```
+
 1. 生成 Certificate Authority (CA) 和 VPN 服务器证书：   
    注： 使用 "-v" 参数指定证书的有效期（单位：月），例如 "-v 36"。
 

docs/ikev2-howto.md

@@ -58,12 +58,21 @@ Before continuing, make sure you have successfully <a href="https://github.com/h
      ikev2=insist
      rekey=no
      fragmentation=yes
-     forceencaps=yes
      ike=3des-sha1,aes-sha1,aes256-sha2_512,aes256-sha2_256
      phase2alg=3des-sha1,aes-sha1,aes256-sha2_512,aes256-sha2_256
    EOF
    ```
 
+   We need to add one more line to that file, based on your Libreswan version. Please run command:
+
+   ```bash
+   $ if /usr/local/sbin/ipsec --version | grep -qs -F "3.19"; then
+       echo " encapsulation=yes" >> /etc/ipsec.conf
+     else
+       echo " forceencaps=yes" >> /etc/ipsec.conf
+     fi
+   ```
+
 1. Generate Certificate Authority (CA) and VPN server certificates:   
    Note: Specify the certificate validity period (in months) using "-v". e.g. "-v 36".